The effects of selective missingness on the size of observed correlations between scores derived from peer assessment procedures were examined with a sample of 719 boys and girls drawn from 57 peer groups in seven schools in Montréal, Québec, Canada or Barranquilla, a city on the northern Caribbean coast of Colombia in Latin America. Peer groups…

Social norms are vital for the functioning of adolescent peer groups; they can protect the well-being of groups and individual members, often by deterring harmful behaviors, such as aggression, through enforcement mechanisms like peer victimization; in adolescent peer groups, those who violate aggression norms are often subject to victimization.…

This study examined variations in the development of classroom aggression popularity norms, as well as the role of homeroom teachers' aggression beliefs and students' perceptions of teachers' support as predictors of such variations. To achieve this goal, a sample of 63 classrooms were assessed at four time points during a school year, in nine…

Data from 790 older school-age (M[subscript age] = 10.2 years, SD = 1.2 years) girls (N = 427) and boys from Barranquilla, Colombia (N = 449) and Montréal, Canada (N = 331) were used to replicate findings reported by Valdivia et al. (2005). This prior study revealed contextual variations in the association between two measures of social behavior,…